Circuit breaker compartment lock operated tripping device



F. E. MYERS Dec. 5, 1944.

CIRCUIT BREAKER COMPARTMENT LOCK OPERATED I'RIPPING DEVICE Filed Nov. 6,1942 8 Shee'cS-SheeiI 2 INVENTOR. /C-z/x /Vyf/es BY Dec. 5, 1944.- F, EMYERS 2,364,465

CIRCUIT BREAKER COMPARTMENT LOCK OPERATED TRIPPING DEVICE Filed NOV. 6,1942 8 Sheets-Sheet 3 INVENTOR Fa /x T /V/f/as BYJMJ m47 Dec. 5, 1944.

CIRCUIT BREAKER F. E. MYERS 2,364,465

COMPARTMENT LOCK OPERATED TRIPPING DEVICE Filed Nov. 6, 1942 8Sheets-Sheet 4 INVENTOR.

Ps2/x T /V/Z'ks BY d @i744 Qa L?? INVENTOR 8 Sheets-Sheet 5 o i? Q KQ mS mkh J .Q3 W 6 Y M w. E. N F. m um Dec. 5, 1944.

CIRCUIT BREAKER CCMPARTMENT Loox OPERATED TRIPPINC DEVICE Dec. 5, 1944.

F. E. MYERS 2,364,465 CIRCUIT BREAKER COMPARTMENT LOCK. OPERATEDTRIPPING DEVICE Filed Nov. 6. 1942 8 Sheets-Sheet 6 INVENTOR.

Dec. 5, 1944.

F. E. MYERS 2,364,465 CIRCUIT BREAKER COMPARTMENT LOCK OPERATED TRIPPINGDEVICE l Filed Nov. e, 1942 8 sheets-sheet 7 /f LV-.J bu

I l I I EN W l/72 l l I" l 170 Lf /63 l /ff #---W l Il' /40 HZ dma l lI' /73 7 l $4@ \\O /67 m /fa /4/ "J/ M /1/ /m M/ 4,

BY fm.

Dec. 5, 1944. F. E. MYERS 2,364,465 CIRCUIT BREAKER COMPARTMENT LOCKOPERATED TRIPPING DEVICE Filed Nov. 6, 1942 8 Sheets-Sheet 8 PatentedDec. 5, 1944 CIRCUIT BREAKER COMPARTMENT LOCK OPERATED TRIPPING DEVICEFelix Edward Myers, Burlington, N. J., assignor to I-T-E Circuit BreakerCompany, Philadelphia, Pa., a corporation of Pennsylvania ApplicationNovember 6, 1942, Serial No. 464,734

8 Claims.

This invention relates to circuit breakers and switch gear, and moreparticularly to protective devices for fully enclosed switch gear havinga swinging front panel or door wherein it is impossible to open thedoorI before the circuit breaker has been tripped and wherein furthermeans are provided to prevent energization of the circuit breakerelements until the door is closed.

In the maintenance and operation of enclosed circuit breakers, it hassometimes been found that a carelessoperator will open the enclosingstructure before thev circuit breaker has been tripped. The tripping ofthe circuit breaker after the door has been opened and the consequentilash has at times caused injury. Also, when the enclosing structure has-been opened after the circuit breaker has been properly tripped, thenit has also been possible for a careless operator to close the circuitbreaker while the door is open and place the same in service position,thus jeopardizing his own safety as well as others.

The primary object of the present invention therefore is the provisionof an enclosing structure for a circuit breaker or other switch gearwherein the door or front panel cannot be opened until after the circuitbreaker has been trippedv open.

Another object of my invention is the arrangement oi' an enclosingstructure for a circuit fore the door can be opened simultaneouslytripsthe circuit breaker open.

Another object of my invention is for the arrangement of the saidlocking means in such a manner that when the front door or panel isopened, the tripping mechanism of the circuit breaker is so arranged asto prevent closing thereof.

These and many other objects of my invention will be apparent, and wherenot apparent will be pointed out in the following description anddrawings in which:

Figure 1 is a side view in elevation of a circuit breaker compartmentwith the near wall or enclosing sheet of the compartment removed.

Figure 2 is a front view in elevation of the lower portion of thecompartment door with the handle operated linkage shown in dotted lines.

Figure 3 is a cross sectional view partly in elevation taken on line3--3 of Figure 2 and looking in the direction of the arrows.

Figure 3a is a View in perspective of one of the bearing members ofFigure 3.

Figure 4 is a schematic view showing the position of the door handle andlinkages when `the circuit breaker is tripped.

Figure 5 is a schematic View showing the door handle and linkages whenthe members have been moved to a position permitting the door to beopened.

Figure 6 is a top plan view partly in section taken from line 6-6 ofFigure l, looking in the direction of the arrows and showing theoperating structure in the lower part of the compartment.

Figure 7 is a fragmentary view partly in section taken on line 1 1 ofFigure 6 looking in the direction of the arrows.

Figure 8 is an enlarged view of the lower section of the internalcompartment structure shown in Figure 1.

Figure 9 is a Viewl corresponding to that of Figure 7 but showing thetripped position of the elements of Figure 7.

Figure l0 is a cross sectional View taken on line IIJ-I0 of Figure 8 andlooking in the direction of the arrows. T

Figure l1 is a cross sectional view taken on line II--II of Figure 8looking in the direction of the arrows and showing the position of theelements when the circuit breaker has been tripped and the door is readyto bevopened.

Figure 12 is a view corresponding to that of Figure l0 showing, however,the movement of the elements to the position where the circuit breakeris tripped while the door cannot yet be opened.

Figure 13 is a fragmentary enlarged view of a portion of Figure 7showing the arrangement of the parts thereof when the circuit breaker isin tripped position while the door is still locked 1n.

Figure 14 is a schematic View in perspective of the various trippingelements and linkages showing the position thereof for tripping thecircuit breaker without permitting an opening of the door.

Figure 15 is a cross sectional view taken on line l5-I5 of Figure 2looking in the direction of the arrows.

Rei erring now to Figure 1, I have here shown a. circuit breakerenclosing structure consisting of a compartment or cell in a switchboard structure.

The compartment I8 comprises upper and lower frame members II and I2 andvertical frame members I3 and I4 which serve as a supporting structurefor the upper and lower enclosing sheets I5 and I6 and the side wallmembers I'I.

The front of the c"ell or compartment ID is closed by a hinged door orpanel I3 which is suitably swingingly supported on one of the side framemembers I3 and is provided with door actuating and opening mechanism 2Band circuit breaker operating mechanism 2i. A common handle 22 may beutilized for each of the operating mechanisms carried by the door.' Theoperation of the handles is hereinafter more specically set forth.

The circuit breaker operating mechanism 2| is a cam which is rotatablysupported in suitable bearings in the front panel or door structure I8and is provided with a central squared opening adapted to receive thesquared end of the handle 22. The squared opening 24 for receiving thehandle end is more clearly shown in Figure 2 immediately beneath asuitable indieating device 25 which is provided with means forindicating the position of the circuit breaker,

` whether tripped or closed.

tion of the circuit breaker to open or closed position while the door isclosed or may have a form such as that shown in Graves Patent No.1,955,- 287 or in Application Serial No. 377,605 both of which areassigned to the assignee of the present invention.

The operating mechanism contained in the housing 34 may be actuated bythe cams to open and close the circuit breaker contacts. The circuitbreaker in Figure 1 is shown in closed position. The links 36 and 31have been extended so that the roller 38 on the pivot therebetween issupported by the abutment 39, This serves to provide a partial supportfor the pin 40 to which one end of the link 42I is secured.

The upper end of the link 42 is pivotally secured by pin 43 to the arm44 which in turn is secured to and operates the contact carrying shaft45. The movable contact structure 4B carried by the shaft 45 may thus beactuated into and out' of engagement with the stationary contactstructure 41 when the shaft 45 is rotated in appropriate directions.

A lever 50 is also secured to the contact carrying shaft 45, the outerend of the said lever having secured thereto one end of the tensionspring 5I, the opposite end of which is secured to the bracket 52carried by the panel 10 of the circuit breaker. The pin 4U which aspointed out above is partially supported through the abutment 39, theroller 38 and links 38 and 31 is 'further supported by the link 55 whichat its opposite end is pivotally secured at 56 to the latch lever 51.

The latching tip 58 of the latch lever 51 is held by the primary latch59 which is supported at its upper end on the pivot $0. The lower end 6Iof the primary latch 59 is engaged by the secondary latch 62. The saidsecondary latch 62 may be a milled shaft rotation of which in aclockwise direction will result in tripping of the circuit breaker.

The type of operating mechanism herein described is quite similar in itsvarious functions to the operating mechanism shown in application SerialNo. 377,605, assigned to the assignee of this invention and forms nopart of the present invention except insofar as the trip elements ofthis type of structure may be integrated with the door actuatingelements to result in a tripping open of the circuit breaker preliminaryto the opening of the door.

`The entire circuit breaker 32 is supported on a panel 18 which in turnis secured to a vertical frame member 'I2 which is slidable, in itsvertical position, to selected positions in the compartment I. Theslidable supporting frame 12 is carried by a suitable extensiblesupporting structure 15 which comprises a pair of pantograph links 11and 18 on each side. Link 11 is pivotally supported on the pin which inturn is carried by the bracket 8I welded to the compartment structure.

The opposite end of link 11 is provided with a pin 83 slidable in a slot84 in a bracket member 85 carried by the vertical frame supportingstructure 12. Link 18 is pivotally carried by pin 88 on bracket 89 whichin turn is carried by the frame 12. The opposite end of link 18 isprovided with a pin and is supported in a slotted bracket similar tobracket 85 which however is secured to the compartment frame.

The mid-point of the two links 11 and 18 are joined by the pin 98 sothat as the frame 12 and the circuit breaker panel 10 are moved towardsthe right, the links 11 and 18 assume an X form as their lower pivotpins move upward in their respective slots. This mechanism will maintainthe circuit breaker panel 10 in a vertical position during itshorizontal movement.

This type of pantograph circuit breaker supporting structure is moreclearly shown and described in Graves Patent No. 1,955,287, as well asin application Serial No. 377,605 both of which are assigned to theassignee of this application. The particular type of slidable supportingstructure forms no part of the present invention. A1- though variousoperations of the present invention relate to the maintenance of thedoor in open position while the circuit breaker is in a test positionwithin the compartment, any type of sliding structure which will supportthe circuit breaker panel in erect condition while it is moved toVarious positions in the compartment -may have any suitable form such asthe formv shown in application Serial No. 421,734 assigned to theassignee of this application. It is obvious,

however, that when the circuit breaker struc- `ture is moved to theright, the movable disconnect contacts 94 and 95 disengage from thestationary disconnect contacts 9| and 92 thus making it possible to testthe operation of the circuit breaker while no current flowstherethrough.

The circuit breaker may be moved horizontally within the compartmentstructure in any suitable manner. At the left hand side of Figure 6 Ihave shown'a simplified means for effecting this operation consisting ofa threaded member rotatable in a suitable bearing in a front bracket IUIsupported at the lower end of the compartmentstructure and at theopposite end rotatable in a suitable thrust bearing |02. The front endof the threaded member is squared at |04 to receive the end of a socketwrench or similar member to eifect rotation of the threaded member |00.A nut ||0 is mounted on the threaded member and is provided with slots-on each side which receive flanges I|2 secured to the lower end of themovable frame supporting structure 12.

Accordingly, when the threaded member |05 is rotated in an appropriatedirection, the nut I I0 is moved outwardly towards the front of thecompartment thus moving the ilange ||2 and thus the frame member '12,thereby moving the circuit breaker panel horizontally and extending thepantograph supporting mechanism. When the threaded member is rotated inthe opposite direction, then the circuit breaker panel and itssupporting frame are moved inwardly and the pantograph supportingstructure is correspondingly collapsed.

The door structure is so arranged that before the same can'be openedvarious linkage mechanisms hereinafter described must be actuated insuch a, manner as to trip the circuit breaker. The tripping action willof course be obtained by rotation of the milled shaft 62 (Figure 1) in aclockwise direction to release the primary latch member 59 which in turnwill permit a collapse of the movable contact sup-porting links.

It is obvious of course that the milled Shaft 62 is operated by anysuitable automatic tripping mechanism which will cause a rotation of thesame under predetermined overload conditions.

The milled shaft 62 also carries an arm |20, the rotation of whichdownwardly will also effect the necessary clockwise rotation of theshaft and hence a tripping of the circuit breaker.

A link |22 is |pivotally secured at |23 to the outer end of the arm andthe opposite end of the said link |22 is pivotally secured by the pin|25 to the lever |26. Lever |25 is rotatably mounted on the fulcrum pin|21 which is carried by-a :bracket |28 secured to the panel 10 of thecircuit breaker. The lever |25 projects through a suitable opening slotor notch in the lower end 'of the panel 10 and comprises an arm |30projecting beyond the rear end of the panel. This larm rests ulpon theupper 'end of a suitable taxppet |32.

yrise `thus depressing the pin |25 at the opposite end of the lever,thus pulling the link |22 down and hence rotating the arm |20 and themilled shaft 62 in a. clockwise direction, thus tripping the circuitbreaker open.

The door opening structure 20 which is to be operated by the handle 22is so arranged that when the handle is moved to unlock the door, thetappet |32 is caused to rise. A tripping bar |35 is provided in thelower part of the compartnient (Figures 1 and 8). The said tripping baris rotatably supported in the back bearing |31 and in the fro-nt bearing|38. This bar may more clearly be seen in Figures 6, 8, 10, 11, l2 and13 and is over substantially all of its length of rectangular orsubstantially rectangular cross section.

The bar is maintained in its various operating positions as seen inFigures 10 and 11 (see also Figure 6), by means of a compression spring|40. One end of the compression spring |40 bears against the pivotedfbearing |4| on the arm |42 extending from the back end of the trippingbar |35. The |pivoted bearing carries a plunger |44 which is surroundedby the spring |40, the said plunger being slotted at |46 to engage thecircumferentially slotted pin |41 carried by the stationary bracket |48secured to the bottom of the compartment. The outer end |50 of thecompression spring |40 is held in xed position with respect to the pin|41 -in any suitable manner, or it may simply bear against said pin.

In Figure 10 is shown the position of the tripping bar when the circuitbreaker is in closed position or when it is so arranged that the circuitbreaker may readily be moved to closed position. In Figure 11, thetripping bar is shown in a position which is rotated counterclockwisefrom the position of Figure 10 where it has actuated the trippingelements.

As will readily be seen from Figures 10 and ll the spring |40 has anover-center action. Thus in rotating the tripping bar |35 from theposition shown in Figure 10 to the position shown in Figure 1l, thespring |40 is iirst compressed for approximately 45 of the rotationwhere it reaches its maximum compression. Then, as the tripping bar |35is furtherrotated to the pcsition shown in Figure 11, the spring |46 maynow expand again on the opposite side of center and thus bias thetripping bar |355v into the position shown in Figure 11.

Suitable stops must however be provided to fix the two positions ofFigures 10 and 1,1. In the absence of such stops, the spring |40 byfurther expansion, say, in the position of Figure 10, would cause thetripping bar |35 to rotate clockwise to an alternate tripping position.Likewise, in the absence of such stops further expansion of the springwhen the tripping bar is in the position of Figure 11 may cause acounterclockwise rotation of the tripping bar |35 to e non-trippingposition.

Asseen, however, in Figures '7 and 9, the tripping bar is provided witha suitable stop element which xes the maximum rotation in eitherdirection. The forward end of the tripping bar is provided with afan-shaped cam |50, the additional functions and operations of which arehereinafter further described.

The cam |50, however, for purposes of this description, is provided withstoep elements |5| and |52. When the tripping bar is in the positionshown in Figure 10, the cam |50 has been rotated to the position shownin Figure 7 where the stop element |5| bears against the bottom sheetyof .the compartment and limits further rotation in a clockwisedirection. When the tripping bar has been rotated counterclockwise tothe @trip position as sho-wn in Figure 11, then the cam l| which isrigidly secured to the tripping bar |35 is likewise rotatedcounterclockwise to the position shown in Figure 9 where the stopelement |52 bears against the vbottom sheet of the compartment and thusprevents further rotation in that direction.

Thus the lposition of the tripping bar |35 in either the trip position.thereof or in the position where it permits operation of the circuitbreaker is fixed rst by the action of the over center spring |40 whichurges the tripping bar to the selected position and secondly by thesto-p elements |5| or |52 on the fan-shaped cam |50 which oppose thecompressive action of .t 1e

spring |40 when the tripping bar has reached f the selected position.

The manner in which the various positions oi the tripping bar |35 affectthe operation of the tappet |32 -to effect a tripping of the circuitAbreaker through the links |26 and |22 is more clearly shown in Figuresl0, i1 and 12. A tripping lever is pivotally supported on a pin |6| andis secured thereon by means of the cot- ,ter pin |162. The pin |6| iscarried by a bracket |63 secured to the under side of the frame 12. Onearm oi the tripping lever .|50 is engaged beneath the tripping bar |35.The opposite arm |01 bears against the lower end of the tappet |32.

Tappet |32 is slidably positioned by the reinforcing bracket |10, anopening being provided through bracket |15 and in the lower end of the`fra-Ine 12. The tappet consists oi a cylindrical rod |13 the upper endof the said rod being at |14 hexagonal in shape and is tapped to receivethe adjusting screw |15 which is locked in position by the lock nut |16.The head |15 of the adjusting screw bears against the under surface ofthe arm |30 of the lever |26 as above described. The adjusting screw |15provides for simplified means of adjustment for any variation in thedimension or" the parts so that these variations may be compensated for.

In Figure l0, the tripping bar |35 is shown in horizontal positioncorresponding to that of Figures 1 and 6 which is the normal operatingposition in which current can be sent through the circuit breaker and inwhich the tappet |32 is permitted to remain in its lowered position toavoid a tripping of the latch 62.

In Figure 11 the tripping bar |35 has been rotated 90 counterclockwise,In this position,the circuit breaker has been fully tripped and thecompartment door may be opened. This counterclockwise rotation of thetripping bar |35 has depressed the end |05 of the tripping lever |60 andhas thus raised the end |01 thereby raising the tappet |32, and alsoraising the end |30 of the lever |26; in-this way the milled shaft 02 ofthe circuit breaker tripping mechanism has been rotated clockwise thustripping the circuit breaker open.

The tripping bar |35 as may readily be seen is now` maintained in thetripping position of Figure 1l by means of the compression spring |40 inthe manner previously described. The apparatus is so designed howeverthat it is not essential to rotate the tripping bar |35 for a full 90turn in order merely to effect a tripping of the circuit breaker. Thelink members |26 and |22 and 'ibe'milled shaft 62 are so arranged that amini- 'abonnee mum of lift :by the atappet |32 ,will 'result 4in .atripping of the breaker. This minimummotion of the tappet y|32 maybeaccomplished by a rota- Vtion yof the tripping bar in acounterclockwise vdirection of not 4more than 35.

This condition is ymore clearly shown in Figures 12 and 13 wherein itwill beseen that the tripping bar has been rotated roughly 35counterclockwise corresponding t0 a similar rotation of vthe .fan-shaped`cam |50. The end |65 of the tripping lever |60 has been forceddownwardly causing a consequent lifting of the end |61 and of the tappet|32 to trip the circuit breaker.

In Figure 13 it will be seen that the fan-shaped cam |50 has likewisebeen rotated to the same degree as has the tripping bar |35. The spring|40 (Figure 12) lhas been compressed but has not passed through centerso that when the rotative force is removed yfrom the tripping bar |35,the spring |40 may expand once more to reset the tripping bar in theposition of Figure y10.

The tripping bar itself is `caused to rotate by the operation of thehandle I22 when it is inserted in the operating mechanism 20 (Figure l).The voperating mechanism for the tripping bar terminates in a pin whichengages a slOt |8| in the ian-shaped cam |50 (Figs. '1 and 9). Theian-shaped cam |50 is rigidly secured to a sleeve |03 (Figure 6) havinga squaredhole |84 adapted to receive a similar squared extension of thetripping bar |35.

A tapped hole |81 is provided for a. -set screw in order to integratethe cam |50 with the tripping bar |35. Any other suitable means ofsecurement of the fan-shaped cam |50 to the tripping bar |35 may ofcourse be utilized, the essential element being that any rotative forcebeing imparted to the cam |50 by the pin |80 should be transmitted tothe tripping bar |35.

The manner in which the pin |80 is operated to rotate the fan-shaped cam|50 and hence to rotate the tripping bar |35 is shown schematically inFigure 14.

A cam member is rotatably mounted on r vthe door |8 in a mannerhereinafter more specifcally described and is so arranged as to beoperabie by the handle member 22. An upper link is pivotally secured at|96 in any suitable manner to the cam member |90. The upper end or thelink passes through a slot |99 in the bracket |01 mounted on the door.In the closed and locked position of the circuit breaker, the outermostend |98 of the link |95 passes through a slot in a bracket 200 securedto the upper portion of the compartment structure.

Similarly, a lower link 202 'is pivotally secured in any suitable manerat the pivot 203 to the cam member |90. apart on opposite sides of thecenter of rotation of the cam member |90 so that the link |95 will beraised when the link 202 is lowered and vice versa. The lower end of thelink 202 is provided with the pivot pin 205.

An additional link 206 is secured to the pivot 205 and extendsdownwardly through the slot 201 in the bracket 208, likewise mounted onthe door i8. The lowest portion 2|0 of the additional link 206 passesthrough a slot in the bracket 2 2 which is secured to the cellstructure.

When now the cam |90 is rotated so that the outer ends of the links |95and 206 pass through the slots in the brackets 200 and 2|0, the door islocked in position to close the compartment. The door cannot be openedluntil the cam |90 ls rotated to a position where the ends of links |95The pivots |96 and 203 are tion of the trip bar shown in Figure 10.

and 206 .are removed from the slots in brackets 200 and 2|2.

A bell crank lever 2|5 is rotatably secured on the door panel I8 bymeans of the pivot 2I6 and has an arm 2I1 the end of which is secured tothe pivot 265 between links 202 and 206. The opposite arm 220 of thebell crank lever 2|5 is pivotallyr secured at 22| to the end of link222. The opposite end of the link 222 is pivotally secured at 224 to theend of the crank 225, the said crank being pivoted at 221 on the'door.

The crank 224 is provided with the pin |80 which projects into the slot|81 of the fan-shaped cam |50 which in turn is mounted on the end of thetrip bar I 35 and operates in the manner previously described.

In Figure 2 I have shown the position of the various operating elementsof Figure 14 when the compartment door is closed and locked in position.Here it will be seen that the links |95 and 2532-226 have been extendedso that they pass through the respective brackets 200 and 2|2 to lockthe door'in. position. In addition, the cam member itself has beenlocked in position so that it cannot be rotated by an unauthorizedperson.

To accomplish this purpose, the cam member is provided with a slot 230,to receive the bar 23| of a key operated lock 232. The slot 230 isopposite the extensible bar 23| in the fully closed and locked positionof the door panel so that a key may be utilized in lock 232 to effectthe engagement shown in Figure 2.

The rotation of the cam towards the locking position is limited so thatwhen the door is fully locked in position, the cam can rotate no furtherin the locking direction and the said limit of rotation alsopredetermining the point at which the slot 230 will come to rest so thatit may be engaged by the bar 23 I.

This limitation of rotation may be obtained in any suitable manner. Thusthe cam |90 may be provide-d With projections 242 and 243 adapted toengage the anglen clip 240 which is secure-d to the cell wall adjacentthe door panel.

The angle clip itself serves as an additional point of securement forthe door since the cam |90 carried by the door rotates behind the angleclip and is released therefrom only when it isl rotated from theposition shown in Figure 2 to the position shown in Figure this therebyprovides a three point locking system for the free edge of the door, atthe top and bottom and at the angle clip 240.

When the cam has been rotated to the fully locked position shown inFigure 2., the projection 242 thereof engages 4the angle clip 240 andprevents further rotation.

In Figure 5 I have shown the position of the cams and linkages when thedoor has been fully unlocked. The cam has here been rotated 90 from theposition shown in Figure 2 so that the ends of 'links |95 and 202-206have been disengaged from the locking brackets 200 and 2I2 and theopposite stop member 245 on the cam |90 has engaged the upper surface ofthe angle clip 240 to limit further movement.

It Will be obvious that before such rotation could take place, the keyoperated lock 232 must be turned so that the bar 23| is withdrawn fromthe slot 230. The'position of the operating linkages shown in Figure 2corresponds to the posi- The position of the operating linkages shown inFigure 5 corresponds to the position of the trip barV shown in Figure11.

In Figure 4 I have shown the arrangement of the operating linkages whichcorresponds to the arrangements of the trip bar shown in Figures 12 and13. Here the cam |90 has been rotated suiciently to cause through thelinkages 202, 2|5 and 222, an effective rotation of the trip bar |35 toeffect the trip of the circuit breaker.

However, it will be seen in Figure 4 that the link |95 and the link202-206 have not been fully withdrawn from their respective lockingbrackets 200 and 2|2 so that the door cannot be opened. It will thus beobvious that the locking mechanism shown in Figures 2, 4 and 5 may underspecial circumstances be used to trip the circuit breaker open withoutunnecessarily unlocking the door.

It will also be clear from an inspection of Figures 2, 4 and 5 and theircorresponding Figures 10, 11 and 12 that the tripping of the circuitbreaker is effected during the unlocking operation and takes placebefore the door is unlocked and hence takes place before the door caneven begin to open.

The cam member may be mounted on the door in any suitable manner topermit rotation thereof by the handle 22. A preferred way is shown inFigures 3 and 15. In Figure 3 I have shown a bearing 250 in the frontdoor panel I8 for the cam member |90.

The bearing itself consists of a cylindrical member welded to the panelI8, the said cylindrical member having a flange 25|. The panel I8 hasbeen drilled to receive the smaller cylindrical diameter 252 of thecylindrical bearing 250 and to provide a suitable support therefor. Thebearing member 250 has a bore 260 to receive the cylindrical extension26| of the operating cam |90.

The extension 26| of cam |90 is tapped at 263 to receivescrews 264, 264which secure the holding washer 266 in place in the counterbore 261 ofthe outer ange 25| of the bearing 250.

The back surface of the cam |90 bears against the inner surface of thebearing 250 and the cam is thus rotatably secured within the bearing 250but, however, cannot escape longitudinally therefrom.

The extension 26| is provided with a squared hole 210 to receive thecorresponding squared shaft 212 on the handle 22. The holding washer 266also has preferably a squared hole although it may have a cylindricalhole to receive the shaft 212 of the handle 22. The bearing member whichsupports the cam 2| which operates to open or close the circuit breakermay be made in substantially the same manner.

In Figure 3a it will be seen that the outer face 25| of the bearingmember 250 is equipped with an L-shaped extension 280 the said extensioncomprising an angular leg 28| and a reentrant ledge 282. The handleshaft 212 is provided with a protruding 1in 283 which when inserted inthe bearing member and rotated in a counterclockwise direction to fullyunlock the door will slide under the reentrant ledge 282 of theextension 280. In this position when the circuit breaker has beentripped and the door fully unlocked force may be applied to handle 22 topull the panel door open. Without such an extension 280, a pull on thehandle when the door has been fully opened will result in the retractionof the handle.

The bearing member 24 which is used for merely opening or closing thecircuit breaker need not of course be provided with a similar extension280 since no pull is to be exerted on the handle to result in anyoperative function when the handle is inserted in said bearing member.

In order to provide for rigid securement of the lever 2I5 and the crank225 on the door panel, a reinforcing bar 285 is secured to the doorpanel having an extension 285 within which the shouldered screw 2I6 maybe mounted. (See Figure 15.)

Similarly (see Figure 8), the actuating crank 225 is pivotally securedto the reinforcement 285 by the shouldered screw 221. Inspection ofFigure 8 will also clearly show the manner in which the pin |80 carriedby the crank 285 may be moved to engage the slotv IBI in the fanshapedcam |50 to operate the mechanism.

By the means herein set forth, it will now be clear that the door cannotbe opened until the circuit breaker has been tripped so that it will beimpossible for the operator to be injured by the tripping open of anenergized circuit breaker when the door is opened. When the panel doorI8 has been fully opened and the inside operating mechanism has beenexposed, there is a possibility that a careless or thoughtless operatormay tamper with the tripping bar |35. A locking mechanism may then beprovided to prevent any unauthorized revolving of the tripping bar |35,especially while the door is opened.

This locking mechanism may more clearly be seen in Figures 6, '1 and 9and consists of a plunger shaped bar 300 secured to the front structuralmember by means of'pins 30|. 302 which extend through the slotl 304 inthe bar 300. Holding washers 305, 305are mounted on the pins on eitherside of the plunger bar 300 and maintained in place by Cotter pins 301,301, thus securing the plunger bar 300 in sliding position upon the pinsh-'302.

The end 3|0 of bar 300 is narrowedto be received by the locking slot 3|2in the supporting sleeve |83 of the cam |50. The end of the pin 302 ismachined at 3|5 to receive and hold one end of the tension spring 3|6,the opposite end of which is supported by bracket 3 I1 on the right handend of *the plunger bar 300. The bar 300 is thus continuously biasedtowards the slot 3|2.

The bar 300 has at its outermost right hand end a vertical shoulder 320which will receive the surface 322 of the angle bracket 323 which issecured to the door panel I8 in any suitable manner as `for instance bythe screws 325. When the door I8 is swung open, the bracket 323 willmove outwardly and will. slip away from the shoulder 320 of the plungerbar 300. The spring 3|6 will thus urge the plunger bar towards thesupporting cylinder member |83 of the cam |50 and thus urge the end 3I0of the bar against the surface thereof.

When a full 90 rotation has been reached as shown in Figure 9, the end3|0 of the plunger bar will enter into the slot 3|2 of the sleeve |03and thus lock the sleeve |83 and hence the trip bar |35 against anyrotation whatever. When the door is closed again, the angle bracket 323will. engage the shoulder 320 and draw the bar 300 to the right againstthe bias of spring 3|6 thus drawing the` end.3|0 thereof out of thelocking slot 3|2 and thereby unlock the tripping bar` |35 so that it maybe rotated.

Thus it will be seen that the door cannot be opened until the trippingbar has been rotated to the position shown in Figures 1l` and 9. Whenthe door is open, the locking element 3|0 engages the slot 3|2 andprevents any operation whatever of the tripping bar |35 until the dooris closed whereupon the locking element 3|0 is withdrawn. The end |04 ofthe threaded element |00, the operation of which will move the circuitbreaker to various positions within the compartment is uncovered whenthe door is opened so that a socket Wrench may be used to draw thecircuit breaker out to its test position in which case the disconnectcontacts are separated at a safe distance.

A pointer 330 is secured to the movable frame 12 in any suitable manneras shown in Figure 6. This pointer may register with two marks 33| and332, indicating respectively the service and the test position of thecircuit breaker, the latter position being that wherein the circuitbreaker has been safely deenergized.

When the circuit breaker has reached the test position wherein thepointer 330 registers with the mark 332, the tripping lever |50 movesopposite the notch 350 in the tripping bar |35. As seen particularly bythe dotted line positions of Figures 8 and 1l, the notch 350 thuspermits the tripping lever |50 to rise to normal position, thus alsopermitting the tappet |32 to drop to its low'- ered position so that thecircuit breaker may be' manually closed to permit observation of itsfunctioning by an inspector. This is necessary since the tripping bar|35 is so arranged that when the circuit breaker has been moved awayfrom the service position, the tripping bar can under no circumstancesreturn to its horizontal position of Figure 10 but remains in theposition of Figure l1. This is accomplished by the provision of an angleclip 355 welded to the bottom of the frame 12 and extending immediatelybehind the shoulder 356 of the tripping bar |35 when the circuit breakeris in service position.

By reason of this position of the angle clip 355, the tripping bar |35may in the service position of the circuit breaker be readily rotated toany desired position. When the circuit breaker is withdrawn from theservice position as shown in Figures 8 and 11, then on the initialmovement of the panel, the lower end of the angle clip 355 movesalongside of the upper part of the tripping bar |35 (see particularlyFigure 1l) and thus prevents the bar from being moved clockwise to itsnormal position of Figure l0. This arrangement assures the maintenanceof the tripping lever |50 in tappet raising position during movement ofthe circuit breaker between the test and service positions. The notch350 is provided with sloping sides so that if in the test position thecircuit breaker has been closed and the operator starts to move iteither towards the front of the compartment or towards the serviceposition, the end |65 of the lever |50 will be depressed and the circuitbreaker latchwill be released.

From the foregoing it will be obvious that the compartment operatingmechanism has been so arranged that the circuit breaker will be trippedbefore the door of the compartment is free to open and is maintained inthat position under all conditions except when the circuit breaker is inpredetermined test position. On movement in either direction away fromtest position. if the circuit breaker has been left closed, it will beautomatically tripped when such movement is initiated.

Since it is desired that the circuit breaker which is to be used inconnection with the mechanism herein described be of the trip freetype,l it will be impossible to make the contacts touch upon anattempted closure of the circuit breaker while the tripping mechanism isin the actuated position of Figure 1.1. In closing the compartment door,it is necessary to hold the handle 22 in its extreme raised orcounterclockwise position so that the actuating pin |80 may correctlyengage the slot I8! of the tripping cam U50. It will be impossible toclose the door if this condition is not satisfied since the design ofthe fanshaped cam l is such that it will not permit the pin to enterinto the compartment in a misaligned position.

Upon closure and locking of the door, removal of the operating handleleaves a surface which is neat and free from any protruding mechanism.

The operation of this device is both simple and safe. Should theinspector or operator attempt to open the door before the circuitbreaker has been' tripped, then' in the process of unlocking the doorand before the door is fully unlocked, the circuit breaker is trippedopen so that thereafter the door may be opened with safety.

It is necessary merely for the operator to insert the handle 22 inposition, holding the same aligned vertically into the opening 2li! `inthe member 26| which is carried by the bearing 25d. He then rotates thehandle counterclockwise with respect to Figure 2 until the position cfFigure is reached, whereupon the door may be swung open.

This operation, as above described, trips the circuit breaker open asthe handle moves through the position shown in Figure 4 and before theposition of Figure 5 is reached. When the door is then pulled open bythe handle after the position of Figure 5 is reached, the circuitbreaker may be racked in and out but the trip bar I cannot be rotatedsince it is held locked ,in position in the manner shown in Figure 9.

` The circuit breaker maybe operated while the door is open only when ithas been racked into a test position Where it is-completely disconnectedfrom the back contact assembly so that it is safely deenergized.

Should the circuit breaker be racked in closed position from the test tothe service position then on initiation of this movement, thecircuitbreaker will be tripped so that at no time can the circuitbreaker contacts be energized or clos-ed while the door is open. Onclosing the door and locking the same, the locking device of Figure 9 isreleased so that the trip bar may b-e operated to its non-trippingposition and the circuit breaker placed into service once more byactuation of the cams 2| 30A An opening 3| 3 may be placed in member it!in line with slot 304 in plunger S when the plunger is in lockingposition. A pad-lock 3M may then be passed through this hole and theslot to prevent unauthorized tampering with the mechanism.

In the foregoing, I have set forth my invention in connection only witha preferred embodiment thereof and in connection with a type of circuitbreaker which I have found readily adaptable to cooperation with theelements of my invention. Many variations both in the type of circuitbreaker and in the manner of connecv tion with the tripping elementsthereof shouldnow be obvious to those skilled in the art, and also manyvariations in the elements of my protective interlocking system whichfunctions to increase the safety of the operator or the inspector shouldno W be obvious to those skilled in the n. art. Accordingly, I prefernot to be bound by the disclosure herein, but only by the appendedclaims.

I claim:

1. A circuitinterrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure effective when the panel is inenclosing position for opening and closing the contacts of saidinterrupter, means independent of said first means for opening saidcontacts, means for locking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operative between a trip'- ping and non-trippingposition, and actuating means on said panel cooperating with an elementof said shaft effective during unlocking movement of the locking meansof said panel to rotate said shaft to the tripping position andoperative during locking movement of said locking means to rotate saidshaft to the non-tripping position and hold said shaft in saidlastmentioned position while said panel is closed.

2. A circuit interrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure'effective when the panel is inenclosing position for opening and closing the contacts of saidinterrupter, means independent of said rst means for opening saidcontacts, means for locking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operable between a tripping and non-trippingposition; a cam on said shaft; and a' crank member on said panel, saidcrank member carrying a pin cooperating with the cam on said shaft andeffective during unlocking movement of the locking means of said panelto rotate said shaft to a tripping position and operative during lockingmovement of said locking means to rotate said shaft to a nontrippingposition and hold said shaft in said lastmentioned position while saidpanel is closed.

3. A circuit interrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure effective when the panel is inenclosing position for opening and closing the contacts of saidinterrupter, means independent of said first means for opening saidcontacts, means for locking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operable between a tripping and non-trippingposition; a cam on said shaft; and a crank member on said panel, saidcrank member carrying a pin cooperating with the cam on said shaft andeffective during unlocking movement of the locking means of said panelto rotate said shaft to a tripping position and operative during lockingmovement of said locking means to rotate said shaft to a non-trippingposition and hold said shaft in said lastmentioned position while saidpanel is closed; said locking means comprising a rotatable member, linksextending from said rotatable member and engageable with lock elementson said panel and said enclosure; and an additional link connected toone of said links at one end thereof and connected to said crank on saidpanel at the other end thereof, movement of said locking means tounlocked position actuating said crank in one direction and movement ofsaid locking means to locking position actuating said crank in saidother direction.

4. A circuit interrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure eiective when the panel is inenclosing position for opening and closing the contacts of saidinterrupter, means independent of said first means for opening saidcontacts, means for l-ocking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operable between a tripping and nontrippingposition; a cam on said shaft; and a. crank member on said panel, saidcrank member carrying a pin cooperating with the cam on said shaft andeffective during unlocking movement of the 'locking means of said panelto rotate said shaft to a tripping position and operative during lockingmovement of said locking means to rotate said shaft to a non-trippingposition and hold said shaft in said last-mentioned position while saidpanel is closed; and means carried by said door panel for locking saidshaft in tripping position when said door is opened.

5. A circuit interrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure effective when the panel is inenclosing position for opening and closing the contacts of saidinterrupter, means independent of said first means for opening saidcontacts, means for locking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operable between a tripping and non-trippingposition; a cam on said shaft; and a crank member on said panel, saidcrank member carrying a pin cooperating with the cam on said shaft andeffective during unlocking movement of the locking means of said panelto rotate said shaft to a tripping position and operative during lockingmovement of said locking means to rotate said shaft to a non-trippingposition and hold said shaft in said lastmentioned position while saidpanel is closed; and means carried by said door panel for locking saidshaft in tripping position when said door is opened; said last mentionedmeans comprising a lock bar, engageable with an opening in said shaft,means biasing said lock bar toward engagement with said opening, and amember carried by said panel engageable with said lock bar when saidpanel is closed for retracting said lock bar against the bias of saidspring.

6. In combination with a circuit interrupter mounted on a vertical panelof insulating material, a stationary enclosure, contacts rigidly mountedin said enclosure, said panel movable horizontally in said enclosure andhaving -contacts engageable with and disengageable from said rigidlymounted conta-cts, said enclosure having a door panel movable to permitinspection of said interrupter, means operable from the outside of saidenclosure for tripping and closing the contacts of said interrupter, atripping member Within said enclosure independent of said first namedtripping means; means for locking said door panel in closed position.;and means operable on movement of said locking means to unlockedposition and before said door panel is opened to move said member to atripping position, and means effective on closing and locking of saiddoor panel to move said member to a nontripping position and to holdsaid member in said last named position While said door panel is inlocked position.

7. In combination with a circuit interrupter mounted on a vertical panelof insulating material, a stationary enclosure, contacts rigidly mountedin said enclosure, said panel movable horizontally in said enclosure andhavingT contacts engageable with and disengageable from said rigidlymounted contacts, said enclosure having a door panel movable to permitinspection of said,

interrupter, means operable from the outside of said enclosure fortripping and closing the contacts of said interrupter, a tripping memberwithin said enclosure independent of said first named tripping means;means for l-ocking said door panel in closed position; and meansoperable on movement of said locking means to unlocked position andbefore said door panel is opened to move said member to a trippingposition; and means effective on closing and locking of said door panelto move said member to a non-tripping position and to hold said memberin said last named position While said door panel is in lockedposition,I the initial unlocking movement of said locking means for saiddoor panel moving said member to said tripping position.

8. A circuit interrupter, an enclosure therefor comprising a movablepanel, means outside of said enclosure effective when the panel is inenclosing position for opening and closing the contacts of saidinterruptor, means independent of said first means for opening saidcontacts, means for locking said panel in closed position, saidindependent means for opening said contacts being operable upon anunlocking movement of said locking means and comprising a rotatableshaft in said enclosure operative between a tripping and non-trippingposition, and actuating means on said panel cooperating with an elementof saidshaft effective during unlocking movement of the locking means ofsaid panel to rotate said shaft to the tripping position and operativeduring locking movement of said locking means to rotate said shaft tothe non-tripping position and hold said shaft in said last-mentioned.position while said panel is closed; said locking means comprising arotatable member, a link extending from said rotatable member andengageable with lock elements on said panel and said enclosure; and anadditional link connection from said rotatable member to said actuatingmeans.

FELIX EDVARD MYERS.

